转换图片 Bitmap To BitmapImage

http://blog.sina.com.cn/s/blog_6e6941e10100n2yn.html
public class GetBitmpIamge
{
public static BitmapImage BitmapToBitmapImage(Bitmap bitmap)
{
Bitmap bitmapSource = new Bitmap(bitmap.Width, bitmap.Height);
bitmapSource.MakeTransparent();
int i, j;
for (i = 0; i < bitmap.Width; i++)
for (j = 0; j < bitmap.Height; j++)
{

Color pixelColor = bitmap.GetPixel(i, j);
Color newColor = Color.FromArgb(pixelColor.R, pixelColor.G, pixelColor.B);
if (newColor == Color.FromArgb(255, 0, 0, 0))
{
newColor = Color.FromArgb(255, 255, 255, 255);
}
bitmapSource.SetPixel(i, j, newColor);
}
MemoryStream ms = new MemoryStream();
bitmapSource.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = new MemoryStream(ms.ToArray());
bitmapImage.EndInit();
return bitmapImage;
}
}